Laboratory Test Overview: What to Expect and What Your Results Mean

Published: August 9, 2026Updated: August 16, 2026

This test identifies anaerobic bacteria growing on a catheter tip to help diagnose infections related to catheter use.

Quick summary

{"This test finds bacteria that grow without oxygen (anaerobes) from a catheter tip","It helps diagnose infections that may be caused by improper catheter care or use","Results help doctors choose the right antibiotics for treatment","A positive result means bacteria were found and need treatment","The test is important for patients with long-term or implanted catheters"}

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC: 105608-4
Short code: BCTAN3
Synonyms: Bacteria Cath Tip Anaerobe Cult org #3
Category: chemistry
Sample: serum
Container: Sterile, anaerobic transport container or anaerobic transport system (e.g., Port-A-Cul vial, anaerobic transport swab system)
Units: N/A
Fasting: false
Population: adult
Sex: all
Age range: 0–120 years
Method: anaerobic-culture
CPT: 87075
SNOMED: 415683008
Specimen volume: Entire catheter tip (typically 5 cm segment of the distal catheter tip) submitted in anaerobic transport medium
Stability: Specimen should be processed within 2 hours of collection at room temperature. If delayed, maintain at room temperature (20-25°C) in anaerobic transport media for up to 24 hours; do not refrigerate as cold exposure is lethal to most anaerobes
Hemolysis max: 500
Lipemia max: 1000
Icterus max: 500
TAT: 48–168 hours
Order: routine

What is this test and what does it check for?

This test looks for anaerobic bacteria on the tip of a catheter. A catheter is a thin tube that can be placed in the body to drain fluids or give medicines. The test uses special methods to grow and identify bacteria that do not need oxygen to survive (anaerobic bacteria).

Your doctor may order this test if they suspect you have a catheter-related infection. Symptoms may include fever, redness, swelling, or pain around the catheter site, or cloudy fluid draining from the catheter. This test helps find the exact cause of the infection so the right treatment can be given.

How is this test performed, and do I need to prepare for it?

During the test, the tip of your catheter is carefully removed by a healthcare professional and placed in a special container. The tip is then sent to a laboratory where it is placed in an environment without oxygen. If any anaerobic bacteria are present, they will grow and can be identified. This process usually takes 2-5 days.

What do my test results mean, and what happens next?

A 'positive' result means anaerobic bacteria were found on your catheter tip, suggesting an infection. A 'negative' result means no anaerobic bacteria were found, but this does not completely rule out infection—other types of bacteria or causes may still be considered. Your doctor will explain what your specific results mean for your situation.

Reference range

No anaerobic bacteria isolated; identification reported qualitatively when positive (e.g., Bacteroides fragilis, Clostridium perfringens, Peptostreptococcus spp.)N/A

Specimen: serum

No special patient preparation required. The catheter tip should be removed aseptically using sterile technique and transported immediately to the laboratory to preserve anaerobic viability

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings2

Frequently asked questions

Is this test painful?

The catheter tip removal may cause brief discomfort, but it is generally not painful. The procedure is quick and done by trained healthcare staff.

How long does it take to get results?

Results typically take 2-5 days because anaerobic bacteria need time to grow in the laboratory. Your doctor will call you with results as soon as they are available.

What happens if bacteria are found?

If bacteria are found, your doctor will prescribe appropriate antibiotics based on the specific type of bacteria identified. You may also need the catheter removed or replaced, depending on the severity of the infection.

Can I still use my catheter if the test is negative?

Your doctor will decide if you can continue using the catheter based on your symptoms and overall condition. A negative result for anaerobic bacteria does not necessarily mean the catheter is safe to use if other signs of infection are present.

Sources

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy